If she won't compete with me, should I pursue a different partner? I would continue group lessons, monthly private lessons with the lady teacher, going to Salsa venues with my W, going to the weeknight ballroom venue by myself or with my W, practicing on my own.
This seems perfectly reasonable, loving and healthy to me, and I think doing this would help you with your R, long-term. Oh, she may b*tch and moan at first (she's quite good at that ), but I think you showing that strength -- that boundary -- would be good for you, long- and even medium-term.
This is probably a discussion for another day, but I'd really like to challenge you on your whole thread title, because I don't think "Love" and "Boundaries" are opposites. Done properly, setting and enforcing boundaries can be